Snap-action switch



1, 1962 c. A. BALL, JR 3,032,623

SNAP-ACTION SWITCH Filed Oct. 19, 1959 k 15 12 Fax. 2 19 57 42 1121 35 6A?) 1Q j 13 &5 34 12 2 35.

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United rates 3,032,623 Patented May 1, 1962 3,932,623 SNAP-ACTIQN SWITCHCharles A. Ball, Jr., Highland Park, Ill., assignor to Cherry ElectricalProducts Corp., Highland Paris, 111., a corporation of Illinois FiledOct. 19, 1959, Ser. No. 847,265 1 Claim. (Cl. 200-67) My inventionrelates to a new and useful improvement in a snap-action switch and moreparticularly to an electrical switch having a contact movable betweencontact bearing terminals.

An object of my invention is in the provision in a switch of thischaracter of a movable switch blade that is caused to be moved with asnap-action between contact bearing terminals.

Another object of my invention is in the provision in a switch of thischaracter of an arrangement of parts whereby the contact pressurebetween the movable contact and a fixed contact is increased prior tothe snapactiou movement of a movable switch blade.

A further object of my invention is in the provision in a switch of thischaracter of a flexible contact blade which in its normalassembledposition is caused to assume a natural wave throughout itslongitudinal length, which wave is responsible for the contact pressurebetween contacts and a snap-action movement of the blade when thenatural wave thereof is deformed.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of partsto be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing the preferred form of construction and in which:

FIG. 1 is an elevational view of my improved snapaction switch;

FIG. 2 is a top plan view of the same; FIG. 3 is a side elevational Viewof my switch showing the cover removed;

FIG. 4 is a side elevational view similar to FIG. 3 but showing theparts thereof in actuated position; and

FIG. 5 is a perspective view of my flexing contact blade in its naturalunmounted condition.

Referring to FIG. 1 I show a housing for my improved switch. Thishousing 10 comprises complementary sections 11 and 12 with the sectionsbeing mounted together in facial relationship by means of rivets 13.Adapted to project out of the ends 14 and 15 of each of the sections 11and 12 is a pair of spaced apart fixed contact bearing terminals 16 and17. Adapted to project out of the opposite ends 18 and 19 of thesections 11 and 12 is one end 20 of a flexing contact blade 21.

As each of the sections 11 and 12 are identical, I will describe butone. Referring to FIGS. 3 and 4 I show therein a side elevational viewof section 11. This section 11 is provided with cavities 22 and 23.These cavities 22 and 23 are separated by opposing triangularly shapedprojections 24 and 25 formed as an integral part of the section 11. Theapex of each of these triangular sections 24 and 25 are suflicientlyspaced apart to permit the positioning therebetween of a portion of theflexing contact blade 21. In the end wall 26 of the cavity 22 there isprovided a V-notch 27 extending transversely to the longitudinal lengthof the section 11. Formed in the end wall 28 of the cavity 23 is a likeV-notch 29 which also extends transversely to the longitudinal length ofthe section 11.

It should be noted that the flexing contact blade 21 is of a lengthgreater than the distance between the V-notches 27 and 29 hereinbeforedescribed. Therefore, when the flexing contact blade 21 is positionedwithin the housing 10 with its one end 30 seated in the V-notch 27, andthe shoulders 31 and 32 formed in its opposite end, positioned in theV-notch 29, the blade 21 will be forced to assume a natural wave such asis shown in FIG. 3. This natural wave in the blade 21 is so formed thatopposite peaks thereof are disposed on opposite sides of thetriangularly shaped projections 24 and 25 in each of the cavities 22 and23. In order to maintain the flexing contact blade 21 in its naturalwaved condition I provide a conical coiled return spring 33. This spring33 sits in a recess 34 formed in the base of the cavity 23. The purposeand function of the return spring 33 will be hereinafter made apparent.

Formed in the section 11 is a passage 35 which has open communicationwith a recess 36 formed in the top wall of the cavity 23. An actuator 37is positioned within the passage 35 and is adapted to be reciprocatedtherethrough. This actuator 37 terminates inwardly of the section 11into an enlarged head portion 38 which is adapt ed to sit in the recess36 formed in the top wall of the cavity 23. This enlarged head 38 isprovided with a nipple 39 which is adapted to engage the flexing contactblade 21 on the side opposite the engagement of the spring 33 with suchblade 21 which is at the highest point of elevation of the wave formedin the blade 21 as seen in. FIG. 3.

In actuating my improved snap-action switch the actuator 37 is depressedso that the enlarged head 38 thereof will force the wave 40 of theflexing contact blade 21 between the V-notch 29 and the projections 24and 25 to be depressed downwardly against the action of the spring 33.When the wave 40 has its highest point thereof indented and depressedbelow the centerline that extends between the V-notches 27 and 29 theflexing contact blade 21 will cause a reversing of the peaks of the wavesuch as is shown in FIG. 4. By the flexing of the restricted naturalwave of the blade 21 into a reverse wave, a snap-action movement takesplace through that portion 42 of the blade 21 which lies in the cavity22 between the V-notch 27 and the apex of the triangular portions 24 and25. By such snap-action the contact 43 carried by that portion 42 of theblade 21 is moved into engagement with the contact 44 and the terminal16 and out of engagement with the contact 45 of the terminal 17. Whenthe moving force is removed from the actuator 37 the reverse waving ofthe blade 21 is accomplished by the return spring 33.

It should be noted that the blade 21 in its normal position hassuflicient end forces applied to that portion 42 by reason of itsdisposition between the V-notch 27 and the restriction of the triangularsections 24 and 25 that there is produced a desired contact pressurebetween the contact 43 and the contact 45. When the actuator 37 isdepressed and the wave 40 is forced to assume a deformed condition thecontact pressure between the contacts 43 and 45 is increased until thesnap-action movement takes place as hereinocfore described.

While I have illustrated and described the preferred form ofconstruction for carrying my invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. I, therefore, do not wish to be limited to the precisedetails of construction set forth, but desire to avail myself of suchvariations and modifications as come within the scope of the appendedclaim.

Having thus described my invention, what I claim as new and desire toprotect by Letters Patent is:

A tease-proof snap-action switch comprising a housing having a pair ofadjacent cavities, internal projections separating said cavities andeach having upper and lower sections formed substantially triangularlyin cross-section with their apexes in abutting relation with respect toeach other, a pair of terminal plates carried by said housing at one endthereof and having portions extending into the adjacent cavity andopposite end portions extending externa'lly of the housing, contactheads carried by said terminal plates in opposed relation with respectto each other in said adjacent cavity, said housing providing inopposite end walls within said cavities aligned V-shaped seats, a switchblade arranged within the housing and extending between said apexes andsaid terminal plates, one end of said switch blade reduced to provideoppositely disposed shoulders and an elongated terminal adapted toextend exteriorly of the housing in a direction opposite to saidterminal plates, said switch blade between said shoulders and the otherend thereof being of a length greater than the distance between saidseats whereby when said switch blade is arranged in said housing withsaid shoulders and said other end thereof in engagement with said seatssaid blade will be undulated longitudinally to provide alternate bowedportions one within each of the cavities, said other end of said switchblade having contacts thereon for alternate engagement with the contactsof said terminal plates, and means for alternately bowing said switchblade to cause the contacts carried thereby to have said alternateengagement with the contacts of said terminal plates, said meansincluding a movable actuator carried by the housing and engaging theswitch blade at one side thereof, and

a coil spring arranged in said housing in alignment withv said actuatorand engaging the opposite side of said blade to resist movement of saidactuator to flex said switch blade in an opposite direction.

References Cited in the file of this patent

